<div class="panel panel-default">
    <div class="panel-heading">
        <h4 class="panel-title">
            <a href ng-click="isOpen = !isOpen">
                <span ng-class="{'text-muted': isDisabled}">
                    {{heading}}
                </span>
            </a>
        </h4>
    </div>
    <div class="panel-collapse collapse" uix-collapse="!isOpen">
        <div class="panel-body" ng-transclude></div>
    </div>
</div>
